标题：Characterization of vegetative inflorescence (mc-vin) mutant provides new insight into the role of MACROCALYX in regulating inflorescence development of tomato
摘要：Inflorescence development is a key factor of plant productivity, as it determines flower number. Therefore, understanding the mechanisms that regulate inflorescence architecture is critical for reproductive success and crop yield. In this study, a new mutant, vegetative inflorescence ( mc-vin ), was isolated from the screening of a tomato ( Solanum lycopersicum L.) T-DNA mutant collection. The mc-vin mutant developed inflorescences that reverted to vegetative growth after forming two to three flowers, indicating that the mutated gene is essential for the maintenance of inflorescence meristem identity. The T-DNA was inserted into the promoter region of the MACROCALYX ( MC ) gene; this result together with complementation test and expression analyses proved that mc-vin is a new knock-out allele of MC . Double combinations between mc-vin and jointless ( j ) and single flower truss ( sft ) inflorescence mutants showed that MC has pleiotropic effects on the reproductive phase, and that it interacts with SFT and J to control floral transition and inflorescence fate in tomato. In addition, MC expression was mis-regulated in j and sft mutants whereas J and SFT were significantly up-regulated in the mc-vin mutant. Together, these results provide new evidences about MC function as part of the genetic network regulating the development of tomato inflorescence meristem.
